This invention relates generally to valves for diverting the flow of fluid from one outlet to another, and more particularly to a side spray diverter valve used in plumbing faucets with a separate hose-connected side spray.
Diverter valves are known in the prior art for a faucet which directs water to either the faucet spout or to a spray nozzle connected to the faucet assembly by a hose. When the spray nozzle is activated, the corresponding drop in water pressure in the spray hose activates the diverter valve so as to divert the water from the normal faucet spout through which it is flowing to the spray nozzle outlet. The water supply is usually from both a hot water line and a cold water line, usually associated with a mixing valve to adjust the water temperature, although a diverter valve could operate with only a single source of water under pressure.
A number of diverter valves or transfer valves are known in the prior art, which have been designed to meet the problems associated with residential water supplies. One problem is that of particulate material in the water. Although the usual residential faucet spout is fitted with an aerator having filters to trap particulate matter, this is not effective in the case of particulate matter passing through the diverter valve which can become trapped between the moving parts and interfere with proper operation. Another problem for diverter valves connected to an outlet attached to a hose, which could become immersed in a sink of dirty water, is the requirement that the diverter valve be of an anti-siphon type. This requirement is found in American Society of Sanitary Engineering (A.S.S.E.) standard no. 1025 stating that there be no back-siphonage of water through the spray or hose when the control valve of the spray is defective or open and a vacuum is applied to the faucet inlet. Further requirements are that a diverter valve meet high temperature and water pressure requirements, that it meet minimum flow requirements both at the faucet spout outlet and at the hose spray outlet when the spray is activated, and that it shall not permit more than a specified leakage at the spout outlet when the hose spray is activated. Therefore, the diverter valve should be constructed in such a manner that it meet these requirements and have provisions for reducing possibility of particulate matter blocking flow passages and affecting the performance of the diverter valve.
A prior art diverter valve is known in U.S. Pat. No. 2,587,961 issued Mar. 4, 1952 to Bletcher et al., who disclose a transfer valve which incorporates an anti-siphonic means to prevent water from flowing backwards from the spray outlet into the water supply line should a vacuum condition occur. The transfer valve incorporates a pressure actuated control valve to divert water at the inlet into the spray outlet when the spray head is actuated, and a separate check valve to prevent flow through the spout outlet should pressure in the water inlet be reduced.
U.S. Pat. No. 2,949,933 issued Aug. 23, 1960 to Moen discloses a spray diverter valve suitable for a water faucet with an inlet mixture of hot and cold water, comprising a sleeve with inlet ports registering with the water supply mixing chamber, and a valve seat controlling flow to the spout outlet. An unrestrained valve piston opens and closes the flow to the spout outlet in response to pressure changes when the spray handle is actuated. Flow to the spray outlet takes place around a piston with a flexible downwardly flaring skirt. Also, pressure in the inlet causes the skirt to seal against the inner surface of the sleeve and movement of the valve seat to eliminate suction through the inlet. The possibility of particulate matter becoming lodged in the clearances introduces the possibility of malfunctions of either the movable valve seat or the piston.
U.S. Pat. No. 4,934,402 issued Jun. 19, 1990 to Tarnay et al. addresses the problem of possible malfunction of the foregoing Moen type diverter valve by reversing the orientation of the skirt on the piston to provide a positive seal, and providing a separate bypass channel to the spout outlet so that there is no flow past the piston, thereby eliminating the possibility of particulates jamming the valve. The bypass channel includes a precision size orifice so that any particulate matter that passes through the orifice will not be trapped. The Tarnay diverter valve requires the addition of another valve and valve seat, thereby adding to the cost of the prior art valves shown by Moen and Bletcher. Since there is a fixed restriction in the bypass line, there is no flow regulation to the spray head. This means that there will be greater flow of water to the spray head at higher pressure resulting in excess flow, and lower flow at lower pressure, resulting in insufficient flow.
Accordingly, one object of the present invention is to provide an improved diverter valve for diverting flow from a spout outlet to a spray outlet when the spray head is actuated, which also incorporates protection against siphoning contaminated water through the spray outlet to the water supply when water inlet pressure is reduced.
Another object of the invention is to provide an improved diverter valve which reduces possibility of jamming any moveable parts with particulate matter.
Another object of the invention is to provide an improved diverter valve with flow regulation to the spray outlet when the spray head is actuated.
Another object of the invention is to provide an improved diverter valve with a minimum of working parts suitable for general use in a variety of diverter valve applications.